61820074566 has 72 divisors (see below), whose sum is σ = 136535719320. Its totient is φ = 20215314432.

The previous prime is 61820074549. The next prime is 61820074571. The reversal of 61820074566 is 66547002816.

61820074566 is a `hidden beast` number, since 6 + 1 + 82 + 0 + 0 + 7 + 4 + 566 = 666.

61820074566 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 48183361 + ... + 48184643.

It is an arithmetic number, because the mean of its divisors is an integer number (1896329435).

Almost surely, 2^61820074566 is an apocalyptic number.

61820074566 is an abundant number, since it is smaller than the sum of its proper divisors (74715644754).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

61820074566 is a wasteful number, since it uses less digits than its factorization.

61820074566 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2178 (or 2116 counting only the distinct ones).

The product of its (nonzero) digits is 483840, while the sum is 45.

The spelling of 61820074566 in words is "sixty-one billion, eight hundred twenty million, seventy-four thousand, five hundred sixty-six".